Former Fianna Fáil TD and minister for health Dr Rory O'Hanlon has died at the age of 92.
He was first elected to the Dáil for the constituency of Cavan-Monaghan in 1977.
A former GP, Mr O'Hanlon was minister for health from 1987 to 1991 when the State's spending on health was under severe strain.
He was re-elected eight more times as a TD.
Dr O'Hanlon became ceann comhairle of the 29th Dáil in June 2002 and remained in that role until 2007.
He retained his seat for a final term from 2007 to 2011 when he was automatically returned as outgoing ceann comhairle.
Before entering politics, he qualified as a medical doctor at University College Dublin and worked as a GP in Carrickmacross, Co Monaghan.
As minister for health, he was forced to make cuts to the health service and bed numbers due to a lack of exchequer funding.
He was appointed minister for the environment in 1991 but lost his senior ministerial role when Albert Reynolds replaced Charles Haughey as Fianna Fáil leader the following year.
In 2011, when Dr O'Hanlon retired from national politics, then-taoiseach Brian Cowen said he was a shining example of all that is good in politics and public service.
He was the father of comedian and Father Ted star Ardal O'Hanlon.
Taoiseach and party leader Micheál Martin said he was deeply saddened to hear of Dr O'Hanlon's death.
He said that he had left a "significant footprint on Irish public life and on the Fianna Fáil party".
"Rory was a very valued friend. I greatly valued his insights and advice since I was first elected to Dáil Eireann.
"He was a gifted doctor, a good listener, a keen observer of people, a caring and empathetic man who sought to improve the lives of his patients and community, and a man who was a natural problem-solver."
The Taoiseach said that Dr O'Hanlon "cared passionately for his community and constituents".
"He advocated for them. He sought to improve their lives. Rory was a natural public representative. He was in politics for all the right reasons: a real commitment to public service," he added.
Mr Martin said the "wonderful storyteller" and "true republican" wore his "many responsibilities lightly, always choosing to speak of those he served, rather than himself".
He expressed his sympathy to Dr O'Hanlon's wife, Teresa, their children, Fiona, Rory, Ardal, Neale, Shane, and Derbhla, his sister, Sr Fionnuala, and the wider O'Hanlon family.
Sinn Féin TD for Cavan-Monaghan Matt Carthy described Dr O'Hanlon as "a pivotal figure" in the political and community life of the constituency for many decades.
Mr Carthy said that he will "be fondly remembered throughout the constituency as well as in his home county of Armagh, and indeed across Ireland.
"Rory will be especially missed in his adopted home town of Carrickmacross, where he was central to every major community development for such a long time."
SDLP leader Claire Hanna MP said that Dr O'Hanlon "was a true friend of the SDLP over many decades.
"His cousin Paddy was one of the six founding SDLP MPs at Stormont," she said. "His life was one of dedicated public service.
"Rory was deeply committed to democratic values and peace. He was a steadfast opponent of those who used violence for political purposes, and throughout his career, he remained a close ally of Seamus Mallon.
"He was a proud son of Oriel (Airgíalla), with a deep connection to the border region and to people in the North.
"He was known for his knowledge of the Irish language and his strong appreciation for the traditions of his community.
"The thoughts of everyone in the SDLP are with his wife Teresa, his children, his former Fianna Fáil colleagues, and all his family and friends at this deeply sad time."
